相关论文: Massive Gravity on a Brane

We consider brane-induced gravity model in more than one extra dimensions, regularized by assuming that the bulk gravity is soft in ultraviolet. We study linear theory about flat multi-dimensional space-time and flat brane. We first find…

In this thesis, we discuss the idea of multigravity, namely the possibility that a significant component of gravity that we feel at intermediate distances (1 mm < r < 10^26 cm) is due to massive but ultralight gravitons. We demonstrate how…

We analyze the propagation of a scalar field in multidimensional theories which include kinetic corrections in the brane, as a prototype for gravitational interactions in a four dimensional brane located in a (nearly) flat extra dimensional…

We consider a modification of gravity at large distances in a Brane Universe which was discussed recently. In these models the modification of gravity at large distances is ultimately connected to existence of negative tension brane(s) and…

We study the regularization of theories of ``brane induced'' gravity in codimension $N>1$. The brane can be interpreted as a thin dielectric with a large dielectric constant, embedded in a higher dimensional space. The kinetic term for the…

We derive the graviton propagator on the brane for theories with quasi-localized gravity. In these models the ordinary 4D graviton is replaced by a resonance in the spectrum of massive Kaluza-Klein modes, which can decay into the extra…

We discuss a Brane World scenario where we live on a 3-brane with massive gravity in infinite-volume bulk. The bulk graviton can be much heavier than the inverse Hubble size, as heavy as the bulk Planck scale, whose lower bound is roughly…

This work deals with gravity localization on codimension-1 brane worlds engendered by compacton-like kinks, the so-called hybrid branes. In such scenarios, the thin brane behaviour is manifested when the extra dimension is outside the…

We consider a brane world scenario which arises as the near-horizon region of a non-extremal D5-brane. There is a quasi-localized massive graviton mode, as well as harmonic modes of higher mass which are bound to the brane to a lesser…

We study whether modification of gravity at large distances is possible in warped backgrounds with two branes and a brane-induced term localized on one of the branes. We find that there are three large regions in the parameter space where…

In brane world scenarios with a bulk scalar field between two branes it is known that 4-dimensional Einstein gravity is restored at low energies on either brane. By using a gauge-invariant gravitational and scalar perturbation formalism we…

We discuss a model in which the fundamental scale of gravity is restricted to 10^{-3} eV. An observable modification of gravity occurs simultaneously at the Hubble distance and at around 0.1 mm. These predictions can be tested both by the…

We discuss the possibility of localizing Einstein gravity on a three-brane embedded in a five-dimensional Minkowski space by giving a space-dependent mass to the graviton. We show that, with an overall fine tuning of the mass profile, it is…

We study a theory of dilaton gravity in a 5-dimensional brane scenario, with a non-minimal coupling of the dilaton to the matter content of the universe localized on the brane. The effective gravitational equations at the brane are derived…

We study the role of the brane-induced graviton kinetic term in theories with large extra dimensions. In five dimensions we construct a model with a TeV-scale fundamental Planck mass and a {\it flat} extra dimension the size of which can be…

Theories with infinite volume extra dimensions open exciting opportunities for particle physics. We argued recently that along with attractive features there are phenomenological difficulties in this class of models. In fact, there is no…

This Thesis presents a study of higher dimensional brane-world models with non-factorizable geometry. It is shown that in the context of multi-brane world constructions with localized gravity the phenomenon of multi-localization is…

We discuss possible variations of the effective gravitational constant with length scale, predicted by most of alternative theories of gravity and unified models of physical interactions. After a brief general exposition, we review in more…

We study braneworlds in a five dimensional bulk, where cosmological expansion is mimicked by motion through AdS$_5$. We show that the five dimensional graviton reduces to the four dimensional one in the late time approximation of such…

We study gravity in backgrounds that are smooth generalizations of the Randall-Sundrum model, with and without scalar fields. These generalizations include three-branes in higher dimensional spaces which are not necessarily Anti-de Sitter…